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CONTENTS This is Volume analysis. II. It contains Chapters V through XI of Part I, the regioIJ-,g.l
SUHl'fARYTABLE OF CONTENTS This environmental Part statement is presented in six parts as follows:
I:
Regional Analysis - A consideration of the Eastern Powder River Coal Basin, its environment, and projected development through 1990. Chapters I - IV. Introduction, Potential Development, Development and Distribution Models, and Description of the Environment . . . . . . . . . . . . . . . . . . Chapters V - XI. Probable Impacts, Mitigating lleasures, Unavoidable Adverse Effects, Alternatives, Relationships Between Short and Long Term Uses, Irreversible Commitments and Coordination . . . . . .
Vol.
I
. ,
Vol.
II
Part
II:
Proposed railroad construction by Burlington Northern Inc. and the Chicago and North Western Transportation Company . . .. . Proposed Company Proposed Company
Vol.
III
Part III:
.. .
mining
and reclamation
by Atlantic
..
.
Richfield
.
Vol.
III
Part
IV:
mining
and reclamation
.
.
by Carter
.
Oil Vol. Coal Vol. Resource Vol. Vol. IV V IV IV
Part
V:
Proposed mining Corporation
.
and reclamation
.
,
.
by Kerr-HcGee
..
. .
I
Part
VI:
Proposed mining and reclamation Development Corp. Appendices.
by Wyodak
Comments received at public hearings and by mail, and responses . . . . . . . . . . . • . . .
Vol.
VI
A detailed
table of contents
of this volume
begins
on the following
page.
T-3
VOLUME II REGIONAL ANALYSIS Chapter
V.
PROBABLE C1~ruLATIVE REGIONAL IMPACTS. Climate . . Air Quality Topography Soils . . . Mineral Resources Water Resources . Vegetation. . • . . . . • . Archeological and Paleontological Values. Historical Values . Aesthetics. . . . Wildlife and Fish Recreation. . . . Agriculture . . . Transportation Networks Land Tenure . . . . . . Socia-Economic Conditions SIGNIFICANT MITIGATING MEASURES Air Quality . . . . . . . Water Quality and Supply ... Resource Disturbance Archeological Preservation. Historical Values . . . . Recreation . . . . . . . Land Use Planning, Zoning and Controls Railroad Construction . . PROBABLE ADVERSE ENVIRONMENTAL EFFECTS WHICH Climate .. Air Quality Topography Soils ... Mineral Resources Water Resources . . Vegetation Archeological and Paleontogical Values. Historical Values Aesthetics Wildlife and Fish Recreation Agriculture . . • Transportation Networks Socia-Economic Conditions CANNOT BE AVOIDED
1-459 1-460b 1-461 1-469 1-475 1-479 1-485 1-504 1-508 1-511 1-514 1-518 1-537 1-542 1-549 1-553 1-554 1-612 1-613 1-617 1-619 1-637 1-640 1-641 1-642 1-645 1-647 1-647 1-647a 1-650 1-651 1-652 1-653 1-655 1-656 1-657 1-658 1-659 1-661 1-662 1-663 1-664
VI.
VII.
T-4
Chapter VIII. ALTERNATIVES TO THE PROPOSED ACTION No New Development Restrict Development . . . . Complete Exportation . . . . Alternate Extraction Methods Alternate Reclamation Objectives Alternate Mode of Distributions . Alternate to Private Development Alternate Utilization Methods . . . Alternate Sources of Energy . . . Production from the Outer Continental Shelf Onshore Production Oil Imports . . . . . Natural Gas Imports Coal (Nationwide) Nuclear Power . . . Geothermal Energy . . Hydroelectric Power . Tar Sands . . . . . Energy Conservation . Other Energy Sources Combinations of Alternatives IX. THE RELATIONSHIP BETWEEN LOCAL SHORT-TERM USES OF MAN'S ENVIRONMENT AND THE MAINTENANCE AND ENHANCEMENT OF LONG-TERM PRODUCTIVITY Agriculture Soil Wildlife Recreation Socio-Economic Conditions IRREVERSIBLE AND IRRETRIEVABLE COMMITMENTS OF RESOURCES Water Resources . . Cultural Resources Aesthetics Lost Production . Loss of Power and Materials Used for Development Loss of Life CONSULTATION AND COORDINATION
1-669 1-669 1-672 1-678 1-679 1-687 1-695 1-702 1-703 1-707 1-708 1-743 1-781 1-793 1-799 1-806 1-817 1-822 1-826 1-829 1-843 1-854
1-859 1-861 1-862 1-863 1-864 1-865 1-867 1-868 1-869 1-870 1-871 1-872 1-873 1-875
X.
XI.
T-5
CHAPTER V PROBABLE CUMULATIVE REGIONAL IMPACTS
The analysis developed in this environmental environmental impact statement is
based on 1990 projections.
The cumulative
impact is quantified, The
to the extent possible with existing probability the pattern at modest is recognized of resource
data, only to this time period.
that, based on current leaseholds and growth will continue
and investments, after 1990, though
development
rates.
Cumulative
environmental
impacts will also increase but will and criteria for
be of variable analysis. decreasing
quantity
as indicated
in the assumptions and predictions
While further projections levels of confidence,
are possible
with ever
the time frame and geographic
area parameters
(Chapter I) were established
at the outset of the analysis.
If differences
occur over time, the impacts analyzed through use of the assumption provide
in this section can be scaled up or down guidelines situation. impact on certain environmental Those most likely to be vegetation, wildlife (Chapter II). This will
and analysis
a better picture of the developing If the magnitude
is scaled upwards,
components affected
would probably
be more than on others. soils, water resources,
are:
air quality,
and fish and agriculture. In the impact chapters it must be strongly whether singular emphasized of the regional and site specific analyses,
that the full impact on the environment, is quantified or qualified to the fullest that would to the that
or cumulative, without
extent assessib1e mitigate, proposed
imposing
any management
constraints
minimize, action(s).
negate or divert these effects as they pertain Such an evaluation is made with the recognition
certain results will not occur since they are precluded management responsibility. The full report,
by agency resource contains
in other chapters,
1-459
the required are approved
and probable
mitigating
measures
to be applied if the proposals
along with impacts which cannot be feasibly avoided. development to the year 1990 within 296 million the study area will tons of coal by
Projected consist of:
ten mines with plans to produce to 12 mines, 858 million
1980, increasing 1,543 million air-cooled
tons by 1985 and 14 mines and and operation of a 330-megawatt
tons by 1990; construction
power plant, and a 250-million air-cooled
cubic feet per day gasification and a 500-megawatt water-cooled
plant by 1980, a 450-megawatt
power plant as well as a second 250 cubic feet per day gasification plant by 1985 and another construction 500-megawatt water-cooled power plant by 1990; 30 miles of coal
of 16 miles of road, 44 miles of powerline,
slurry pipeline, of powerline, of powerline various
140 miles of rail line by 1980, 20 miles of road, 164 miles
145 miles of rail line by 1985, and 24 miles of road, 225 miles and 150 miles of rail line by 1990, all of which will cause on the environment construction and its individual and permanent, of: components. from these develop-
impacts
Employment,
resulting
ments will cause population
increases
27,000 by 1980, 42,000 by 1985 and in population will require
47,000 by 1990 in the study area. associated increased facilities
These increases sanitary
such as schools,
land fills, sewage plants, environmental impacts. Popu-
social services,
all having additional six-county
lation in the surrounding ately:
area is projected
to increase
only moder(
10,000 by 1980, 11,000 by 1985, and 13,000 by 1990.
It is acknowledged
that not all environmental
impacts associated
with this development exported Indiana,
are confined
to the State of Wyoming •. If coa L-d.s Colorado, Illinois,
from the study area to such places as Arkansas, Iowa, Kansas, Louisiana, Nebraska, Oklahoma
and Texas, impacts
1-460
from energy impacts
conversion
will occur
in those areas.
The exact nature
of these
is not reasonably
foreseeable
due to the inability
to fully antici-
pate how and under what conditions It should be noted in electric impacts that the impacts outside
the coal and energy will be utilized. resulting from consumption of coal to the the in
power plants
of the study area may be similar power generation to the degree
of consumption
of coal for electric with respect
within
study area, varying relation impact
essentially
of impact
to environmental
conditions
existing developed
in those areas.
Environmental
of the use of coal and energy at the time other major
in the study area will be are required or as necessary
analyzed
federal
actions
in these states to meet
their environmental
quality
act requirements.
1-460a
Climate Development plants, and disturbance significant changes of a number of coal mines, power plants and gasification of significantly large areas of land surface may cause affect weather and climate. areas do affect climates; and
that could detrimentally
Recent precipitation. therefore, knowledge
studies indicate However
that large urban-industrial
studies have not been conducted
in semi-arid
potential concerning
effects are inferred precipitation
from theoretical
relationships
mechanisms
and studies of climate modifica-
tion in other areas. Two potential may lead to significant climate. in natural major consequences inadvertent of large scale energy development of the regional weather and
modification
These are increases
in atmospheric
particulate
loading and changes mechanism. loading
land surface characteristics Some evidence indicates
which affect the precipitation
that changes of atmospheric
particulate
and alteration
of the earth-atmospheric
energy balance may contribute
to creation
of drought conditions 1972; Mitchell
in semi-arid climates 1973).
(Charlson and Pilat 1969; Bryson Reduction in precipitation could and
1971; Huff, Changnon on agricultural the region.
have severe affects
productivity,
mined land reclamation
water supplies within
1-460b
Air Quality Complex source air pollution Development disturbances pollutants. of numerous coal mines, power plants, residential areas and air
of large areas of land will create multiple Since air pollutants originate
sources of various effective
from many sources,
control
would be more difficult Development particulate hydrogen oxidants,
than if a single pollution
source were involved. dust and other suspended such as
actions as outlined
could generate
matter from physical
activities
and chemical pollutants
sulfide,
sulfur oxides, nitrogen trace elements
oXides, carbon monoxide,
photochemical operations.
hydrocarbons,
and radionuclides
from processing
These pollutants conditions
from complex sources may have an adverse impact on existing air to the study area. Impacts could increase rapidly
in and adjacent
during the period of 1974 to 1980 (seven new mines, a new 330-MW power plant, a gasification pipelines, plant, 27,000 increased powerlines, population, 230 miles of new rail line, roads, and 1980~1985 (two new mines, 129 more and
with 8,900 acres disturbed)
two new power plants, one new gasification miles of roads, rail line, powerlines possibly
plant, 15,000 more people,
and 10,900 more acres disturbed)
level off during the 1985 to 1990 time period
(two more mines, one more
power plant and 5,000 more people,
and 9,200 more acres disturbed).
Plant stack emissions Potentially, possible the most serious cumulative impact on air quality, with is from stack gases plants.
adverse impact on humans,
animals and vegetation,
emitted by four new coal-fired Emissions hydrogen
power plants and two coal gasification oxides, carbon monoxide, and particulates.
include sulfur oxides, nitrogen sulfide, photochemical Projected development oxidants
hydrocarbons,
during the period of 1974 to 1980 shows con(MW) power plant at Wyodak and retirement of
struction
of a new 330-megawatt
1-461
units
1, 3 and 4 of the Neil Simpson Unit
Station.
Assuming
the new plant
and Neil
Simpson annual
5 (20-MW) meet New Source at Wyodak could be:
Performance 1,600
Standards
(NSPS), projected (P), 15,700 (NO )' x
emissions
tons of particulates oxides
tons of sulfur
dioxide
(S02)' and 12,400
tons of nitrogen
During plant to produce
this same time period about 250-million power plant)
construction
of a coal gasification This plant 23,800 tons of
cubic
feet per day is expected. to produce 39,500 yearly,
(with 325-MW sulfur
companion 11,400
is expected oXides,
dioxide,
tons of nitrogen
tons of hydrocarbons with NSPS and Wyoming
(He),
Air
and 2,100 Quality
tons of particulates. Standards.)
(Assuming
compliance
Emission
By 1985 projected and a 450-MW of 4,400 nitrogen power plant
development which
will
include
a new 500-MW
power
plant, emission
at Wyodak
could produce
an estimated
yearly
tons of particulates, oxides. Also a second
40,400
tons of sulfur
dioxide,
and 30,600
tons of
coal gasification
plant
is projected
by this time.
This plant will
have a type and amount
of emissions
similar
to the plant projected and Wyoming Air
for the 1974 to 1980 time period. Quality Emission Another 1990. 21,400 This plant Standards.) 500-MW coal-fired
(Assuming
compliance
with NSPS
power
plant
is expected
to be in operation
by
is expected
to have emissions and 16,100
of 2,300 tons of particulates, oxides. (Assuming
tons of sulfur dioxide, with
tons of nitrogen Emission
compliance
NSPS and Wyoming
Air Quality cumulative
Standards.) during the period 1980 to
Some projected 1990 are shown plants in Table
potential 1.
emissions
Quantities
are based
on the assumption
of new power gasifi-
(other than at Wyodak) and emissions
of 500-~fW size, meeting maximums
250 million permitted
cubic feet/day
cation plants, Performance Standards.
under New Source Air Quality Emission
Standards
for Steam Generators,
and Wyoming
1-462
Based on expected power plants
siting
of new plants, plant)
the areas near Gillette (one gasification
(two
and one gasification affected
and Douglas
plant)
could be adversely northwest
by cumulative
stack emissions.
With a prevailing by
wind direction
(upper level),
other
towns that could be impacted Guernsey, Torrington,
such emissions Wheatland, However, where
include }loorcroft, Lusk, Newcastle, Wyoming; likely Custer,
and Sundance,
South Dakota;
and Scottsbluff,
Nebraska. sites,
most
impacts would
occur within
10 to 20 miles
of the plant
pollutant
concentrations
are usually
highest,
and this would make Gillette
and Douglas
most vulnerable.
Vehicle
and equipment
emissions of the study area and attendant 47,000 by 1990) will Engine emissions population increase
Industrialization
(27,000 by 1980, 42,000 by 1985, combustion engines of all types. hydrocarbons, These
increase result oxides
use of internal in the addition and sulfur oxides
will
of carbon monoxide, to the basin residents, air.
particulates,
nitrogen
emissions
are potentially
harmful
to the health and equipment
of basin emissions
vegetation
and animal
life.
}luch of the vehicle Table 2 gives
will be contributed cumulative
by railroad emissions
locomotives.
some estimated
locomotive
for 1980, 1985, and 1990.
Dust and similar
particulate
matter dust and similar from described particulate matter (coal dust, The
Increases fly ash dust, increased
in airborne
etc.) will result
development will
activities.
possibility
of coal fires and wildfires
increase
the possibility Pollutants
of additional resulting
toxic pollutants
in the air, especially
from coal fires.
from coal fires will be similar Airborne particulate matter
to those from a coal-fired
power plant. cause
could reduce visibility and periods
and possibly
traffic
accidents
during periods
of inversions
of high winds.
1-463
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1-465
High winds are frequent but inversions 15 times per year. Particulate matter
over two-day periods may occur as many as could also contribute with potentially to human allergies harmful chemicals. the
and similar irritations
and coat vegetation
Based on the prevailing impact from the increased and towns of Gillette, and Wheatland, Summary Identification possible Wyoming; airborne
upper level wind direction particulate Douglas,
(northwest),
matter could affect the comrrlunities Guernsey, Torrington
Moorcroft,
Lusk, Newcastle,
and Scottsbluff,
Nebraska.
and quantification
of impacts with precision and a quantitative
is not performed.
until each system has been designed
analysis
Prior to construction ducted. However,
of each of the facilities,
such an analysis will be concertain
based on assumed rate and type of development for the study area.
qualitative
impacts can be predicted Industrialization
and development
of the study area will result in
a decline
in ambient air quality.
A general decline will occur from 1974 to The rate of
1980, with a more serious decline during the 1980 to 1985 period. decline is expected development
to level off after 1985, since by this time the major will have leveled off with only minor increases proposed
projected
for the 1985 to 1990 time period. constant
The decline of air quality will remain fairly (1985-1990). soil and coal dust in areas to the
for the rest of the time period Increased
plant stack plumes and haze from disturbed within the basin and possibly
will result in poorer visibility east and southeast Emissions a long time period. reported vegetation of the basin.
could cause localized Damage to ponderosa
damage to vegetation pine after exposure
and animals over to S02 has been Similar and
(HEW, Air Quality Criteria
for Sulfur Oxides, January 1969).
is found in the Black Hills National Forest around Newcastle
1-466
Sundance,
Hyoming and Custer,
South Dakota;
the northeast
portion of the Thunder
Basin Grassland Ponderosa experience plants
in the vicinity
of Upton and Osage, and in the Rochelle Hills area. The Upton and Osage areas already originating from betonite
pine is prevalent a reduction
in these areas.
in air quality due to emissions Addition of emission
in the vicinity.
from the study area may compound on vegetation and animals are to determine
the impact in that vicinity. not well understood possible
Effects
of emissions
at this time, and research
efforts are underway
adverse effects. Trace elements, including radionuclides, contained in coal burned by Such and
power plants in the study area may be released with stack emissions. emissions could have a detrimental little scientific effect upon soil, vegetation,
animals,
man although environment.
information
exists as to their effects on the
An increase precipitation Bormann
in atmospheric
sulfur is believed
to have resulted
in acid
in the northeastern Emission
United
States as reported by Likens and (S02) by power plants and gasifiin the
(1974).
of sulfur dioxide
cation plants proposed
for the study area could cause a similar problem including
study area and have an adverse effect on the environment, fish, and metal structures is not considered likely. oxidants (as reported
plants, this
by Likens and Bormann).
However,
Photochemical emissions
(smog) may be formed when nitrogen
oxide from power
from power plants combine with certain hydrocarbon plants and sunlight. plant emissions. could have injurious This pollutant
emissions
gasification
may form from proposed
and gasification
Emissions
and toxic effects on humans working plants in case of accidents the basin there
or or
living in the vicinity
of power and gasification inversions. occurring
during periods of severe or repeated is a probability
Throughout
of a two-day inversion
15 times per year, and a
1-467
five-day inversion persistent winter
occurring inversions
four times a year. -- Hearings statement
(Observations 6-26-74.)
by Marwitz
indicate
Impacts on health
could result from long or repeated during inversion Present episodes.
exposures
to any severe air contamination
ambient air quality
in the study area is good, but it will sources as industrialization
decline with the development takes place.
of complex pollution
1-468
Topography The removal of coal during mining operations of the land surface to varying will decrease altitude
degrees and thereby locally create sharper reNew landforms will emerge from coal of spoil materials and to
lief or flatten the slope of the land. removal owing to placement
and type of reclamation
erosion and redeposition
of spoils.
Surface mining will increase
soil move-
ment, change drainage patterns features.
and size, shape, and position
of topographic
Spoil ridges from mine cuts will be subject locally within pits. and require
to erosion, and erosion
may increase
Both water and wind are active agents of some form of control in the vicinity of
erosion and deposition mining operations.
Mining of coal, 296 million 1.5 billion
tons by 1980, 858 million
tons by 1985 and shape of the an
tons by 1990, will significantly this coal.
impact the topographic
area mined to recover estimated
By 1990 surface mining will have impacted
14,000 acres.
Each year the slow pace of mining
thick coal, even at of the
a high annual rate of 118 million area that will be disturbed. coalbeds
tons, alters only a small fraction large mining operations
For example,
which remove
about 60 feet thick to produce
17 1/2 million
tons of coal annually
would disturb dependent
only about 165 acres per year.
At any period about 445 acres, necessitates and excluding operation.
upon the amount of overburden would be disturbed
prestripping
roads and facilities, Such a situation mined,
by each mining-reclamation
could comprise
100 acres being prestripped, and reseeded.
165 acres being production
and 165 acres being smoothed
With an estimated
of 118 million annually period,
tons of coal per year, an average of seven operating mines could
disturb as much as 3,000 acres in a single year, but over a IS-year probably not more than an average of 1,200 acres. The surface would also be altered, but to a lesser degree, by
construction
of 24 miles of new roads and 150 miles of new rail lines by
1-469
1990.
Disturbances
from this type of activity will involve about 3,600 Some alteration of land surface will also result from conMining and
acres by that year.
struction of gasification removal of clinker, activities
plants, power plants, and reservoirs.
sand, and gravel to meet construction
needs of these Acreage impacted
will also cause minor changes to the land surface. is indeterminate at this time.
by this construction
The removal of coalbeds, ranging
in thickness from 20 feet to 120 feet,
will result in an overall lowering of the land surface on which this removal takes place. The average overburden thickness which covers the coal ranges the overburden is broken up and
from a few feet to 200 feet. turned over which increases however,
During mining,
its volume by 20 percent.
This increase in volume,
is not enough to compensate
for the removal of thick coalbeds. in altitude which could result from averages 149 feet and the The 100 feet of
Figure 1 gives an example of the decrease coal removal.
In Part A of Figure 1 the overburden
coal seam averages coal is removed. average altitude
100 feet for a total thickness of 249 feet. The overburden is increased
20 percent in volume or from an decrease in (100 feet)
thickness of 149 feet to 179 feet.
The corresponding between
of the land surface is the difference (30 feet) or 70 feet. tolerances
coal thickness
and the increased volume spoils because of mining
Some coal remains with the of coal); thus,
(90 to 95 percent recovery produces a maximum
this example of 100 percent coal recovery A reduction coal is mined.
depression.
in altitude of the land surface can occur wherever changes in the coal mining area from
Some average altitude
north to south in the study area are about 54 feet at the North Rawhide mine (see Part IV), about 68 feet at the Wyodak mine (see Part VI), about
36 feet at the Black Thunder mine
(see Part III), about 38 feet at the
1-470
A
200-foot ...---overburden line
A
E Ievati on above sea level 149 feet 100 feet coo I - average
Overburden
_ average
wyodak-Anderson
1_4--Clinker zane _--, Present land surface
4100 4000 3900
Average Final
drop in - 65 feet
---------_- ----------- I--t
elevation
..•...
mining
ct. u
•... --..•...
_---
\
..•.
---_/
//
/
//
"''/
'
'
2
Coal
B
200-faot overburden line
B'
Elevation abo ve sea level 117 feet
avera e
o verbu
rden - avera ge
erson coo
50 feet
o a ~ n
Clinker
--i-zone
4500 4400 4300 4200
Average Final mining cut elevation
drop in - 21 feet
Present
land surface
-1---------------' 2
o
o
1000
2000
[
3000
I
4000
I
5000
I
Feet
Horizontal
scale 5X
Verti cal exaggeration l-Conditions 2-Conditions cut-by-cut smoothly slopes. before mining
after mining; overburden is replaced on a basis (assuming 200-foot wide cuts) and graded; remaining walls are graded to 3:1
Figure 1 Diagrammatic Sections Showing Potential Changes in Topography Resulting From Surface Mining
1-471
Jacobs Ranch mine mine.
(see Part V), and about 28 feet at the proposed Rochelle operation illustrated in Figure 2 shows
A typical mining-reclamation
the surface before mining,
the placement
of spoils, and the change in altitude
of the land surface after mining coal in the southern part of the coal mining district. The reduction Here a similar undulating surface may remain after mining.
of the highwall
covers the coal but leaves a small lake in a
residual depression. In some areas where the coalbed is very thick, such as the Wyodak bed around Gillette, not be available and the overburden is thin, sufficient overburden may
to fill the final mining pit.
This partially
filled final depressions
pit will result in the formation throughout the thick coal area.
of lakes or partly waterfilled
East of Gillette, Donkey Creek may be caused by coal mining
partly ponded or trapped in this broad depression as indicated by pre- and post-mining altitudes
along the creek (see Part VI). appearance of the area may the result
Besides a general lowering be changed. Assuming no reshaping
of topography,
of spoil but only smoothing,
will be a broad lowering of the land surface that ends in a long narrow trough at one end of the mine. This is the final pit and highwall. cliff-life Terrain
remains rolling but subdued because scape cannot be recreated. ing undisturbed
or abrupt breaks in the land-
The final landform may be similar to the surroundsmoothed and ravines
area unless the spoils are drastically from ridges
filled by material
(see North Rawhide mine, Part IV) channels and considered terrain This
Mining causes changes in drainage patterns by altering surface slope or gradient. Truck and shovel operation, produces a smoother, presently
by most of the mining companies, that is locally more favorable
lower-gradient erosion.
to revegetation
and decreased
type of mining operation affects a smaller area per year, results
in closer
1-472
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1-473
control of the final surface altitude mining. existing storms. The smooth terrain decreases channels, Although and minimizes
and allows optimum recontouring channeling and headward
after
erosion of from thunder-
the effect of sheetwash decreases
resulting
truck and shovel operation unprotected
the size of the miningan
reclamation available
operation,
broken sandstone
in spoil piles produces
source of fine sand particles.
At wind velocities
above 20 miles per
hour, saltation becomes an effective
means of transport
and removal of the sand. road material, bare
Wind can easily erode loose dust from broken playa material, spoil piles, and soil stockpiles protected by water or grass. if these temporarily material exposed
surfaces are not
Windblown
could form small local dunes,
such as the high level sand dunes near Glenrock, which would add a new dimension and shape to the landscape. Construction the rights-of-way. if a maximum of roads and rail lines will alter topography along
This change in surface is especially is maintained.
true of rail lines
grade of one percent
This causes deep cuts in
the landscape, right-of-way.
ranging from 40 to 102 feet deep on the proposed mainline Roads will require cuts, but they will be of less magnitude
than caused by the railroad.
1-474
Soils Development a significant major impact of coal resources on soils within and attendant facilities will cause
the area disturbed operations
by mining. to remove
The
impact will
result
from actual mining
296 million tons by 1990.
tons of coal by 1980, 858 million This will 14,000 result in disturbance
tons by 1985 and 1,543 million of the topsoil
and mixing
on approximately microover a
acres by 1990.
Disturbance
will alter which
soil characteristics, have been established
organisms
and soil climate time span. period. rate.
relationships The current Impact
long geologic
level of soil productivity increases
will be lost to the acceler-
for an indefinite increased mining
on topsoil
in proportion period
The topsoil
disturbance
per five-year to 5,000
ates from 2,700 acres
in the 1974 to 1980 period Some properties
from 1980 to 1985 will be destroyed 0.3 percent by of
and 6,300 from 1985 to 1990. mining on 14,000
of topsoil
acres by 1990.
Thiu represents Further mining
approximately extend
the surface that level.
in the study area.
would
the impact beyond
Mining coalbeds. horizons,
involves
removal
of large volumes will result
of overburden
to reach of soil in bringgrowth.
Removal
of overburden
in complete
alteration
parent material
and soil characteristics. such as boron, which
It could result may be toxic
ing to the surface At completion from what
elements,
to plant
of mining
operations,
soil structure
will be completely Table
different some for
it was prior
to start of mining will be disturbed
operations.
3 presents
idea of the volume coal.
which
over the 14,000
acres mined
1-475
Table 3 Cumulative Year 1980 1985 1990 Volume of Overburden Disturbed Cubic Yards
Million
266.4 772.2 1388.7
In addition mining,
to the area of soil which will be disturbed will also result from construction lines, mine facilities, pipelines
by actual
soil disturbance
of railroads, gasifica-
access roads, transmission tion plants,
power plants,
coal slurry pipeline,
and new housing
facilities. soil
Much of this disturbance surface.
will result in permanent and permanently
loss of productive
Soil surface disturbed
removed by these activities
is shown in Table 4.
The impact of permanent
soil surface loss is greatest con-
in the 1974 to 1980 time period when 4,800 acres are lost to facility struction. Table 4 Cumulative Soil Surface Acres Disturbed and Permanently Removed from Production Cause of Disturbance Facilities
&
Year 1980 1985 1990
Rights-of-Way 3,100 6,000 7,500
Housing 3,100 6,100 7,500
Total 6,200 12,100 15,000
Permanently Removed 4,800 (77%) 7,900 (65%) 9,500 (63%)
Without knowing basis, it is difficult
the precise
location of the disturbance
on a yearly
to determine
which soil associations
may be impacted.
Since locations are known with a fair degree of accuracy for 1980, disturbed
1-476
acreage
by soil associations is based
were calculated.
The data shown for the subseTable 5 includes acreages
quent years disturbed
on a simple proration
formula.
by all types of activities permanently removed
from 1980 to 1990.
The table also inwith the data
cludes acreage available
which
cannot be separated
at this time
(April 1974). will result in fine grained soil and parent perme-
All of these disturbances material ability being exposed
to wind and water
actions.
Soil productivity, runoff,
and infiltration
rates will be reduced, which is almost
increasing constant
soil erosion area,
and sedimentation. will
vlind action,
over the entire
cause fine soil, silt and clay particles air quality and adding resulting to soil loss.
to be lifted Prior
into the atmosphere of exposed fine
reducing soils,
to revegetation
soil erosion
from high intensity of gullies. accelerate
storms will remove Alteration
materials channels
and can result and increased
in formation will
of stream and
velocity
erosion
of stream banks
cause headcutting
of the streams. population
This will
add to soil loss and sedimentation. (27,000 by 1980, 42,000 to soil values. Greater soil on
Increased
within
the study area
by 1985, and 47,000 by 1990) will cause other losses recreation losses. soils. Even though reduced place Basin, on 0.6 percent
!
use, originating
from more population, vehicle
will
cause additional serious impact
Any increase
in off-road
use could
cause
land is reclaimed,
soil will be lost and productivity As this loss will Powder take Coal
of the study area by 1990.
in probably
the most productive
area of the Eastern
River
the loss could be significant.
1-477
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